My 300 has had the banjo bolt cleaned (by me) fairly recently. It made a difference, but not a big one. I haven't adjusted the valves yet, or messed with the ALDA. The car is very slow from a stop, but once it hits about 1800-2000 rpm, it takes off and accelerates very well. With a high-rpm launch, my manual transmission 240D could probably beat it to 20 mph, but then the 240 needs second gear, and it would be all over after that.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.